For a long time Bitcoin has been the de facto cryptocurrency of the darknet, where its pseudonymity can be made more obscure by mixing transactions using specially designed tumbling services. But the blockchain provides an immutable record and – as attempts by law enforcement to track transactions have evolved, and technology savvy analysis firms have emerged – users are looking for ways to improve their privacy. Webroot, a security company which uses machine learning to identify cyberthreats, predicts Bitcoin may be replaced by privacy-centric cryptocurrency Monero, as the preferred currency of ransomware merchants on the darknet. Monero uses ring signatures in clever ways to bulk together transaction inputs and outputs so that all possible spenders appear “equiprobable”. A couple of weeks ago dark marketplace AlphaBay announced it would be integrating…